Conventional pharmacological treatments for bipolar disorder will be permitted (e.g. Lithium, anticonvulsant mood stabilizers, antipsychotics, antidepressants, anxiolytics/hypnotics, etc.). Medication regimens will remain stable throughout the duration of the study. Enrollment into the study is voluntary. Eligible subjects will provide written informed consent. Study information and consent procedures will be provided by personnel other than the primary treatment provider. Subjects will be enrolled from the outpatient Mood Disorders Psychopharmacology Unit, University Health Network, University of Toronto. Illness characteristics will be obtained from the patient interview and hospital medical records.